7MM Rem Mag Load Data

[Jethro76]

I have just reloaded some 7MM Rem. Mag. rounds with 53, 55, and 58 grs of IMR 4320(only powder available) and 140 gr Nosler AccuBond. I shot them through a cronograph and got an average FPS of 2882 fps 53 gr, 2952 fps 55 grs, and 3051 fps 58 grs.

I was looking to push the bullet over 3200 fps.

Is it possible to go above the 58 grs (80% of case full) or should I stay with the 58 grs.
I am new to reloading so I don't know the pressure limits to keep it under.
I realize from my recent research that the 4320 is a fast burning powder.
I have my rifle sighted in at 300 yards. and want to be able to make just small adjustments to shoot out to 600 yards.

 

[wapiti25]

I would find some 4350 from IMR , Hodgdon, or Accurate. I have used a lot of IMR 4350 in my 7mm Mags. The 4350 powders are showing up at some online dealers.

 

[ShootDots]

With those bullet weights, IMR 4831 is one of the BEST powders for the 7 mag.. It is "fairly" temp stable, will drive the 140 class bullets VERY fast and it is a powder the 7Mag seems to love..

 

[wapiti25]

Midsouth shooter supply has IMR 4350 in 8# and Cabela's has it in 1#.

 

[Jethro76]

I was able to obtain some RL19 powder. The Nosler website load data says it will push the 140 grain AccuBond over 3300 fps with 65.5 grains.

Has anyone had some expirance with this powder and can give me some advice.

 

[22BRGUY]

Might want to check out reloadersnest.com

 

[Deton8tor]

I have shot RL19 in a 7 Mag with fair results, but RL 22 will do better. And, as most have suggested IMR 4350, IMR 4831 , H4350 or H4831 will do better all round.

 

[Jethro76]

Thanks for everyones help. I will shoot some test rounds this week and see how they go.
I called to every reloading store with in 80 miles of my home looking for IMR 4350, RL19, and RL22. The only powder I could find was the RL19 and it was 70 miles from my house.

I guess when the primal fear the U.S. is feeling about ammo goes away I will be able to shop around for the perfect combo. Until then I will shoot and reload what I can find.

 

[Jethro76]

So I reloaded some with 66 grains of RL19 powder and the 140 grain AccuBond which Nosler says should be pushing just under 3300 fps with 65.5 grains.

Well with a 3 round average of only 3040 fps out of my weapon I am totally lost.
What did I do wrong???

 

[nastynatesfish]

Manuals are just rough guides. A lot of stuff goes into velocity out of a given rifle. You need to work up a max load in YOUR rifle do it in 1/2 grain increments. I load one round each and take them out and shoot. Usually from about mid charge to 1 or 1-1/2gr over book max. Shoot, check brass for pressure sign and continue. That way I know the ceiling for my rifle with that bullet. You'd do better with 4831. I use H4831. Used 19 and 22 but they are dirty. H4831 shoots good and is cleaner.

 

[nastynatesfish]

Also. Give some specs on your rifle. What's the barrel length. Mine is 26" and I run my 140 bergers over 3200

 

[XTR]

Well with a 3 round average of only 3040 fps out of my weapon I am totally lost.
What did I do wrong???

Nothing.

One thing you will find is that published MV numbers are very very optimistic, and the ones you see on some websites are down right insane (e.g., a 22" 308 pushing 175s at 2800 kind of insane). Factory barrels may tend to run a little slower than the custom ones.

Don't get overly wrapped up in the MV thing. Find the load your rifle likes with that bullet and shoot it there. A deer is going to be just as dead whether the bullet is going 3300 or 2800 at your muzzle if you are able to put it in the right spot.

 

[sbhooper]

So I reloaded some with 66 grains of RL19 powder and the 140 grain AccuBond which Nosler says should be pushing just under 3300 fps with 65.5 grains.

Well with a 3 round average of only 3040 fps out of my weapon I am totally lost.
What did I do wrong???

There is nothing wrong with that velocity. I load 139 Hornady Interlocks to 3100 fps using an under-max load of Reloder 22. It shoots sub-half-minute and smunches deer. If that load gives you the accuracy that you want, then run the ballistics on it so that you know where it shoots and go with it. That Accubond will do great things at that velocity.

 

[Magic stick]

I have just reloaded some 7MM Rem. Mag. rounds with 53, 55, and 58 grs of IMR 4320(only powder available) and 140 gr Nosler AccuBond. I shot them through a cronograph and got an average FPS of 2882 fps 53 gr, 2952 fps 55 grs, and 3051 fps 58 grs.

I was looking to push the bullet over 3200 fps.

Is it possible to go above the 58 grs (80% of case full) or should I stay with the 58 grs.
I am new to reloading so I don't know the pressure limits to keep it under.
I realize from my recent research that the 4320 is a fast burning powder.
I have my rifle sighted in at 300 yards. and want to be able to make just small adjustments to shoot out to 600 yards.

 

[troupe]

RL-26 will get you there if you can find it.

 

[std7mag]

I use RL19 with the 139gr SST, 140gr Nosler Ballistic Tips & 140gr Berger VLDs.

Don't get hung up on the velocities!

I don't even get my chrono out till after i've found the powder charge from what my target is telling me it likes.
Then seating depth.
Then i'll load up 10 rounds & shoot over the chrono, record that. Then shoot 600-800 yards & true the velocities.
But that's just for having my ballistics calculator spot on.

 

[john 800]

Go on midwayusa and set up am account, go through the powdeers and set notifications for powders mentioned.
You should be able to come up with something that will be acceptable with those powders until you can find something ideal. Ramshot and accurate powders seem to be a little more available at the moment.

 

[john 800]

Magpro is available at midway and powder valley. I haven’t looked up data with that weight but it Is probably a better match than what you have now

 

[hoz53]

Magpro is available at midway and powder valley. I haven’t looked up data with that weight but it Is probably a better match than what you have now

jethro was asking about this back in 2014